Cardiff Splott Road

Ultimate Client

Network Rail

Main Contractor

Carillion

Type of Piling

Contiguous & Bearing

Diameter

750mm

Depth

11m-23m

Project Difficulties and Restrictions

The project required the construction of piles within a height restriction of 4.5m beneath an existing bridge. The works were to be carried out below live road traffic and also adjacent to a live railway.

The strata comprised a cementitious sand material with water ingress encountered at 4m requiring both hard digging and long casings.

The Martello Solution

Martello utilised 2 of their low headroom MP4000 series rigs enabling works to be carried out under the existing bridge, to install the new foundations in advance of the bridge removal, thereby reducing the programme.

The piles were excavated under water using digging buckets and a bypass auger, the piles were then tremmied and the water pumped into waste tanks ready to be PH monitored and treated prior to disposal.

Specific Project Features

Martello was required to construct 35no, 750mm diameter contig/bearing piles to depths of up to 23m whilst working to a tight programme to meet the possession and bridge lift.

Future Potential

The Martello rigs enable rail and road bridges to be replaced and repaired with minimal disruption to transport by allowing new foundations to be installed without removing the existing structure.

The compact nature of the Martello rigs allows multiple rigs to be employed to meet programme requirements.